[PATCH] D69842: [InstCombine] canonicalize shift+logic+shift to reduce dependency chain

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri accepted this revision.
lebedev.ri added a comment.
This revision is now accepted and ready to land.

Okay, thanks, LG.



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Comment at: llvm/lib/Transforms/InstCombine/InstCombineShifts.cpp:321
+  auto matchFirstShift = [&](Value *V) {
+    return match(V, m_OneUse(m_Shift(m_Value(X), m_APInt(C0)))) &&
+           cast<BinaryOperator>(V)->getOpcode() == ShiftOpcode &&
----------------
This innermost shift only has to be one-use iff `Y` is not constant.


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https://reviews.llvm.org/D69842